function  s1_generate_a_series_of_files(){
for i in {1..100};
do
echo $i> /tmp/new_file$i;
done
}
function s2_list_4_files_in_long_format_about_account_and_group(){
l s -l/etc/{passwd,shadow,group,gshadow} |sort
}
function s3_find_items_related_to_given_username(){
grep -h$1/etc/{passwd,shadow} | sort
}
function s4_find_items_related_to_given_group_name(){
grep -h $1 /etc{
group,gshadow} |sort
}
function s5_create_groups_for_given_group_names(){
groupadd rnd
groupadd itoperation
}
function s6_create_users_and_set_their_group_as_required(){
useradd adam
useradd bob
useradd calvin
useradd david
useradd edward
usermod -a-G rnd adam
usermod -a-G rnd bob
usermod -a-G rnd edward
usermod -a-G itoperation calvin
usermod -a-G itoperation david
}
function s7_change_users_shell(){
usermod -s /usr/bin/sh adam
usermod -s /usr/bin/sh edward
}
function s8_set_password_shange_policy(){
passwd -n 10 -x 60 -w 10 adam
passwd -n 10 -x 60 -w 10 bob
passwd -n 10 -x 60 -w 10 david
passwd -n 10 -x 60 -w 10 calvin
passwd -n 10 -x 60 -w 10 edward
}
function s9_set_password_for_five_users(){
usernames=(adam bob calvin david edward)
passwords=("$1" "$2" "$3" "$4" "$5")
for i in $(seq 0 4);do
echo "${usernamees[$i]}:${passwords[$i]}" |sudo chpasswd
done
}
function s10_lock_bobs_password(){
usermod -L bob
}
function s11_include_adam_into_wheel_group(){
sudo usermod -a-G wheel adam
}
function s12_change_files_permission(){
for i in {1..100};
do
filename="/tmp/new_file${i}">$filename
if(($i%3==0));
then
sudo chmod 640$filename
fi
done
}

